1. Field of the Invention
This invention relates to a dental distractor or and particularly to a dental distractor for rapidly correcting severe front teeth crowding and protrusion in orthodontic treatment.
2. Description of the Prior Art
Front teeth crowding and protrusion is an unsightly defect happened to many people. An orthodontic treatment is usually needed to correct this defect. For some other reasons, such like after making some specific dental operations, orthodontic treatments may also be needed to correct teeth problems.
Although there are many reasons which may need to proceed orthodontic treatments, we only take one example to illustrate the steps for performing a conventional orthodontic treatment. Hereunder is an example to perform a conventional orthodontic treatment for severe anterior teeth crowding or protrusion. Such a conventional orthodontic treatment generally includes the following steps:
1. Dental operation (for example, extracting the first premolars or other operation).
2. Mounting a barrel band on the molar and having a steel wire bore formed on a side wall of the barrel band.
3. Adhering a bracket on the surface of the anterior teeth to be treated and having a steel wire slot formed on a sidewall of the bracket.
4. Initial teeth leveling by engaging a steel wire between the steel wire bore and the steel wire slot under desirable tension. Depending on the alignment of teeth, this step may last about three to six months.
5. Retracting canine backward to make room for anterior teeth alignment and leveling. This step may last about four to six months for children and seven to eight months for adults.
6. Retracting anterior teeth to level the protruding teeth. This step may last about six months.
7. Fine adjustment of occlusion and tooth angulations. This step may take about three to six months.
Total conventional orthodontic treatment time thus will take one and a half to two years. It is too long a time for most patients. It is not esthetic to wear braces for such a long period and it is very burdensome for the patients to maintain their oral hygiene as well. It also is very inconvenient and time-consuming for the patients to visit orthodontist""s office to make periodical adjustment in such a long period.
Same applicant has been disclosed a dental distractor (U.S. Pat. No. 5,873,715) which can reduce orthodontic treatment time. However, it has the deficiency of being too complicated and bulky in structure. It is particularly annoying to put it in the mouth which is delicate and sensitive (for example, the mouth after dental operation). It is prone to hurt mucosa and even causes oral ulcer. Moreover, the dental distractor disclosed in U.S. Pat. No. 5,873,715 can not be used together with conventional steel wire treatment (e.g., use steel wire to correct teeth alignment as mentioned above). Thus, there is still a room for further improvement.
It is an object of this invention to provide a dental distractor that can greatly reduce orthodontic treatment time to alleviate patients trouble and inconvenience. In addition, the dental distractor disclosed in this invention should also be able to use together with steel wire treatment.
It is another object of this invention to provide a dental distractor that can either pull two teeth toward each other for correcting teeth having gap therebetween, or push teeth away from each other for correcting teeth being too crowded.
This invention may be used for correcting front teeth crowding or teeth alignment correcting after dental surgery or too large gap between teeth with or without the first premolar extracted.
According to a preferred embodiment of this invention, the molar at two sides of the patient are mounted respectively with a barrel band which has a steel wire bore and an engaging bore formed on a side wall thereof. The anterior teeth have conventional brackets adhered thereon. Each bracket has a steel wire slot. Then a steel wire is engaged with the steel wire slots and has its two ends fastened to the steel wire bores. The dental distractor of this invention has a front joint member, a rear joint member and a screw bar. The front joint member has a round hole member passing through one end of the screw bar and a holding member engageable with one end of the steel wire. The rear joint member has a screw body engageable with another end of the screw bar and a C-shaped hook engageable with the engaging bore of the molar bracket. The screw bar has a screw head for turning the screw bar so that the front joint member may be moved toward the rear joint member. Consequently the steel wire will be pulled and move the anterior teeth for correcting purpose.
In another aspect of this invention, the C-shaped hook is mounted on the front joint member while the rear joint member has a plurality of holding members for engaging with the steel wire. Turning the screw bar will move the rear joint member toward (away from) the front joint for teeth correction and leveling.